What I Want for My Birthday
by Queenie Mab
Summary: Nico accidentally comes across an idea in one of Will's medical textbooks and now he can't think about anything else!
1. Chapter 1

**Disclaimer**: All recognizable characters and themes are the property of Rick Riordan from the world of Percy Jackson and the Olympians. I am not making any money from this work of fiction. I'm just playing around in his sandbox.

Happy Belated Birthday, Nico!

XxxX

Nico's hanging out in the infirmary, waiting for Will's shift to end, just leaning against the wall beside the desk, blending in with the shadows. He can hear murmuring coming from behind a partition, but can't make out the words. He can see Will and another camper's silhouettes through the fabric blocking the exam table from the rest of the room and figures it's going to be a while when Will appears to be selecting an assortment of supplies from his portable cart.

Glancing at the desk, Nico spots a medical textbook, open and face down, its spine bent and nearly broken. He picks it up and starts reading, his face heating up as his eyes fly across the title **Prostate Health and Massage Techniques**. When he reads the words: _carefully crook the inserted digit in a come hither motion_, Nico shuts the book and drops it on the desk like it's burned him, his face in flames, his pants tight.

"I'll be out in a sec!" Will calls, shocking Nico to the realization he's just given away his presence and – he looks back at the book, his lip curling – lost Will's place in his textbook. It will be so obvious that Nico's just been reading about … that _procedure_ and he snatches the book up again and thumbs through the center pages until he locates it, then replaces it facedown. There. At least he covered his tracks. And none too soon as Chiron wheels into the infirmary behind him to take over for Will.

Nico studies the ground and blends in with the shadows on the wall as he passes, then ducks out the door, figuring he'll catch up with Will after he finishes.

XxxX

It's only a few minutes later when Will meets him on the big house porch.

"Hey, there you are!" he says, throwing an arm around Nico's shoulders and squeezing him in a sort of half-hug. "Have you thought any more about what you want for your birthday? Eighteen is a milestone year."

Nico feels his face heat up, but covers it with a scowl. He couldn't give a rat's ass about his birthday and has attempted to make that clear to Will half a dozen times already.

He shrugs out of Will's embrace, but takes his hand to keep him from pouting. "C'mon, lets go back to Hades cabin before anybody notices."

It isn't that he doesn't want to be seen holding hands with Will, he's gotten over most of his hang-ups since they've been going out the past three years, but if they hurry, they might avoid being asked to supervise the younger campers and with Will's infirmary rotation, it's hard to find any time alone at camp.

As they walk across the green, Nico releases Will's hand and falls behind while Will natters on about their plans to attend the University in New Rome the upcoming fall. He can't help himself, his mind is still back on that dratted textbook. The page it was open to, the bent spine, he wonders if Will has ever performed that procedure on anybody in camp. He frowns. It shouldn't bother him if it is a legitimate medical thing, but for the life of him, he can't fathom why any young demigod would require it. He's not jealous or anything, he tells himself. It's not like doing butt stuff is something he wants. But it has been three years and Will has never brought it up.

And then he walks into Will who has stopped in his tracks. He's looking at Nico with a raised eyebrow and that godawful gleam in his eyes that means Nico has some explaining to do.

"Alright, spill. What's freaking you out tonight?"

"Nothing," Nico says. "Why would you think I'm freaking out?"

He turns to look as Will points behind them, then furrows his eyebrows at the sight of his own footprints in the form of dead and blackened patches of grass.

He turns back and bumps Will's arm as he starts to move past him. "It's nothing, drop it."

But Will grabs him by the belt loops and pulls their hips together, making Nico flush. With their faces close, nearly touching, Nico can smell Will's tropical scented shampoo and it relaxes him. He huffs, going for indignant, but it comes out sounding aroused, more so than he thinks he ought to be. He stops Will from asking him about what's going on in his mind by kissing him right there in the middle of the green.

XxxX

The following night, they're hanging out in the rec room, watching Titanic, and instead of paying any mind to the movie, Nico finds himself shifting uncomfortably on the couch, his mind again dwelling on what it would feel like to have Will's fingers up his ass, _moving in a come hither motion_. Sometimes he really hates his hormones for making him hard every time the idea breezes by. Several times a day.

Will brings him back to the present by grabbing his hand, his eyes wide and glued to the screen. Nico looks too, trying to focus on the movie and failing. Instead, he pulls his handkerchief out of his pocket, tucks his arm around Will, settling against him. He's prepared to hand it over when Will starts getting weepy. He's just happy to be close, enjoying the movie in his own way, tending to Will's tears.

XxxX

Afterwards, when they're safely back in Hades cabin, Nico gasps as Will kisses up his neck, his thigh wedged between Nico's legs, pressing against his groin, and breathing hot and heavy. The scent of arousal is thick in the air. If Will keeps going like he is, Nico's going to come in his pants.  
He squeezes his eyes shut, lips trembling, trying to drown his tortuous brain, to turn off the idea of butt stuff and be satisfied with their usual exchange of handjobs. The last thing he wants is to embarrass himself in the heat of the moment by asking about it. He bangs the back of his head against the door of the cabin. Why is he so drawn to the idea? Shouldn't it disgust him? Is he turning into a depraved pervert?

He's cold all of a sudden and opens his eyes. Will has stopped kissing him, and taken a step back, his forehead creased in the middle as he studies Nico.

I"What? Why'd you stop?" Nico asks, reaching for Will's hips and pulling him back until they're back where he wants them to be.

"You didn't seem to be into it," Will murmurs against his neck, just under his ear. He pulls back until they're face to face. "You've been different the past few days. Is it because I keep pestering you about your birthday? I keep thinking I'm doing something wrong."

_Styx_! Why does Will have to be so observant all the time? "What? No. It's not…"

And then Will takes his hand and pulls him across the room to his bed. They sit side by side on the edge. Dread pools in Nico's gut, his arousal waning. Stopping to talk midway through a heavy makeout session can't be a good sign. He looks over at Will, at the severity of his expression.

"Talk to me. If I'm not doing anything wrong, why does it feel like you're pulling away, shrinking back when I'm ramping up?"

Nico's face is in flames. He's going to have to just spill it. Being with Will for as long as he has has taught him that hiding his insecurities or assigning judgements to Will always backfires like nothing else. He's had to dig himself out of a hole dug from doing just that more than a few times. He's surprised Will stuck around despite the pitfalls, ready to hear Nico out when he finally decided to talk about it. His heart flutters when he looks into Will's eyes. He's got it bad for this guy. He takes a deep breath and releases it.

"I um, I dunno ... I was thinking … All right. I'm just going to say it." He narrows his eyes at Will. "No judging."

Will nods, but Nico can tell he's completely puzzled. Nico stares at his hands in his lap. "The other day, I was waiting for you to finish up in the infirmary and I picked up the book you had left on the desk. I started reading it …"

Will makes an odd sound, like he's clearing his throat and trying to swallow at the same time. "The chapter on prostate health?" he chokes out, his voice growing higher-pitched toward the end of the sentence.

Nico looks up at him, smiling despite his own embarrassment at the sight of Will's face blushing pink and looking like he's trying his damnedest not to act embarrassed. The fact he's completely failing at it, actually bolsters Nico's courage to keep talking.

"Yeah. ... and I can't get it out of my head." He looks away, focused on the shimmering reflection of the greek fire torches in the obsidian floor.

Will makes a grunting sound. Nico looks over to find him squirming, pulling a leg up on the bed, like he's trying to do anything to get comfortable. Dropping his eyes to Will's lap, Nico understands why; Will's still incredibly turned on and he's trying not to scare Nico off by downplaying it. It has the reverse effect. Nico's heart picks up again, his body thrumming with adrenaline, with desire.

"Did it … I mean. I haven't actually … " Will exhales as if he's rolling his eyes at himself. "I've never done that to anybody. It's not the sort of thing that would likely ever come up in camp … I just." He takes another deep breath. "It's just like, something that ... I'd like to, you know … someday."

Nico raises his eyebrows, smirking. Will tries to come across as confident in front of other people and mostly succeeds, but he's got insecurities that run just as deep as Nico's and it's a comfort to see them. It makes Nico feel like he's not the only one looking like an idiot in an effort not to.

"You'd like to what, Will?" Nico asks, a smile slipping onto his lips. He puts a hand on Will's thigh, smiling wider as he watches Will's adam's apple bob.

"I don't want to do anything that will jeopardize what we have." Nico nods his appreciation. "But I think about sex … a lot. And one day … Oh gods." His face goes bright red.

Nico leans over and bumps their noses together, just a nudge, relieved as anything to feel Will's hands settle on his hips. "I do too. I want to do it."

Will wets his lips, breathing faster, and Nico pushes him until he's lying on his back and climbs on top of him, tucked between his legs.

"What …" Will breathes. He moans, eyes rolling up as Nico shifts his hips and presses their groins together again. "What do you want to do?"

Nico smashes their lips together in an all-consuming kiss, his body overheating, and then drops his face alongside Will's and whispers in his ear. "I want to have sex. I want to find out what's so great about this prostate thing, why I can't stop thinking about it even though my brain is telling me I shouldn't."

Will chuckles, his breath huffing over Nico's cheek. "Don't listen to that part of your brain." He shifts his hips upwards, making the urge to grind until they come return in sharp relief throughout Nico's whole body. "Oh!" Will says, panting, hands gripping Nico's hips tighter and bumping their groins together harder and faster.

Nico holds onto the sides of Will's head, hands in his hair, his face shoved into the hinge of Will's neck. He pushes his hips back, taking control of the pressure until Will cries out, stiffening underneath him and setting off Nico's own orgasm. It crashes over him, his hips jerking as if they have a mind of their own, bucking against Will until he's totally spent and sticky.

His body still shuddering, Nico rests his head on Will's chest, coming back down. "I know what I'd like to do for my birthday."


	2. Chapter 2

The day starts out all wrong. What else was new? While Nico practiced sword play with Butch in the arena, Cecil ended up falling from the climbing wall and dislocating his arm and Lou Ellen was burned by lava when she tried to help him get up. So instead of spending his birthday with Will as they had planned, Nico wiles the hours away helping Butch with the Pegasi while Will is stuck in the infirmary. It's one of the downsides of dating the only year round Apollo camper: when people get injured, he and Chiron are the only available healers to trade off shifts.

It's not that Nico dislikes helping Butch, but horses have never liked him. And shoveling the stable while Butch handles the grooming since the Pegasi don't want Nico near them just underscores how being a child of Hades still carries a stigma.

He finishes up and returns to his cabin to shower and get ready for bed. Hades knows when Chiron will take over in the infirmary or if it will even happen before curfew. He climbs into bed, pushing down his disappointment. They can try again tomorrow. He sweeps his hand through the air, dimming the wall torches.

Just as he closes his eyes, a knock sounds at the door. It makes his heart jump into his throat, but he schools his face, not wanting to get his hopes up for nothing, and climbs out of bed.

It's Will. But more than that, it's Will freshly out of the shower, his hair still wet and steam rises off him in the cool night air. He's wearing a clean green surgeon's shirt and bermuda shorts despite the fact it's January. Nico pulls him inside and closes the door, unable to stop himself from savoring the scent of Will's coconut shampoo.

"Sorry I'm so late. But nobody saw me headed this way and Chiron said he'd take the night shift. Lou and Cecil are only staying overnight and Chiron said they'll be fine by morning so..."

Nico smirks. It's inexplicably cute how Will won't shut up when he's nervous, and for some reason, seeing Will nervous makes Nico feel more calm and in control.

"So you're saying you want to sleep over."

Will nods, his cheeks going pink.

Nico looks at the backpack slung over Will's shoulder. "And you brought your supplies so if we want to give that er, _procedure_ a try, we can?"

Will nods again, blushing an even deeper pink.

Nico thinks this just might be the best possible birthday present in the world and hesitates only a fraction of a second. He hopes the accidents that his friends had suffered to enable this treat were not, in fact, deliberate acts from any of the gods. He shoves the thought to the back of his mind. There's no sense in dwelling on it.

He drags Will over to his bed, leaving him standing by the foot and feeling a little bit high at the sight of Will's flushed face. He smirks as he pulls his shirt off, pauses a moment, then drops his pajama bottoms and climbs onto the bed.

"You coming?" Nico asks as Will seems to be frozen in place, his eyes huge.

Nico can't help it, he's eighteen, as of today; he's more than ready to step things up a notch, and rendering his too-hot-for-his-own-good boyfriend speechless feels pretty damn good. He rests his back against his pillows, entirely on display and tucks his hands behind his head while he waits for Will's brain to get with the program.

Will blinks a few times, a sheepish grin spreading across his face as if he's just realized he's being a total idiot standing around staring when he could be joining in.

Nico watches him round the bed, unslinging his backpack, and then looking around for somewhere nearby to put it. Nico moves his left hand, holding his arm out straight, palm up, and raises a slab of polished obsidian from the floor beside the bed. It's the perfect height to retrieve things without getting up.

Will smiles at him, then flushes all over again, his ears and neck strawberry red. He looks away and focuses on pulling supplies out of his pack and placing them on the table.

"Do you want me to cover up?" Nico asks, wrinkling his forehead. He's not sure if maybe he's pushing Will too far too fast or if Will is really as into the idea as he is.

Will swallows as he finishes unpacking, then drops the pack on the floor. He takes a couple of deep breaths and turns to face Nico, his professional demeanor in place.

"I only want to make sure that you are comfortable. Do you have any questions before we start?"

Nico shivers at the realization of what Will is doing. He wants to do it like it's actually a medical procedure which explains why he put on a surgeon shirt even though he's clearly showered and off-duty. And fuck it all that the idea of doing this as doctor and patient doesn't make him half hard without any effort. He casts around for a question to ask, any question. Normally patients would want to know what the hell the doctor is going to do to them, right? Maybe an explanation of what the supplies laid out on the table are for?

Damn, his boyfriend is good … acting all innocent and flushed so Nico would push back and try to ramp him up, stripping himself of his clothes and offering himself up like a slab of meat only for Will to turn around and take charge. He narrows his eyes and bites his lip, and then sees Will's eyes sparkle behind his professional persona. Okay. As long as they are both on the same page, Nico supposes he'll go along with it.

He glances at the table, at a small handful of what look like the tiniest condoms he's ever seen. He picks one up and raises a curious eyebrow. "Now, I know you sometimes think you don't quite measure up, but I've seen your dick, Will. This isn't going to fit."

Will's lips twitch at the corners of his mouth, but he maintains his composure. "Those are finger cots. I'll use them for the, uh … procedure."

It sends another thrill through Nico's spine as Will's face pinks up again. He nods and puts the finger cot back on the table. "What's the tube for?"

Will picks up the tube in question, uncaps it and peels the foil from the tip, then hands it to Nico. "Lubrication. The rectal tissues are delicate and easy to tear. The lube will make them slick and prevent damage."

_Holy Aphrodite._ How in Gaea's soulless body is Will able to just say that with a straight face? Nico hands the tube back to Will and nods again. "Okay." He hesitates. "How do we start?"

Will pulls a towel out of his backpack and hands it to Nico and then retrieves a bottle of lotion and rubs some into his palms. "Lay the towel on the bed and then lie face down so it's positioned under your hips.

Nico does it. He's not quite sure what he's in for, and tenses as he settles on his stomach, his cheek pressed to the sheet, watching Will put the finger cots on his index and middle fingers.

Will climbs onto the bed beside Nico and settles a hand on his back, then leans in close so they're face to face. "You okay? We can totally stop if you want, any time."

"Do _you_ want to stop?" Nico asks. He doesn't want anything of the sort, but if Will doesn't want to do it, he's certainly not going to force him.

Will shakes his head, his bangs falling into his eyes, entirely breaking character. "Gods no. I'm so afraid I'll get overeager and push you too far and … and I don't want that. Really though. If you need me to stop or if it hurts, especially if it hurts, tell me right away."

Nico twitches his lips in a small smile. He doesn't want to admit it, but Will is really good at reading him, at knowing what to say to put him at ease. "Can I have a kiss before you turn back into my doctor?"

Will grins, his cheeks dimpling, and wets his lips with his tongue, and damn if that doesn't make Nico want him even more. He lifts his head, meeting Will's lips, kissing soft and slow, his heart fluttering, and then rests his cheek back against the sheet. Will pulls away, sitting on his feet, rubbing his warm palm over Nico's back, massaging his muscles, and before Nico gives himself over to the massage, he spots Will subtly adjusting his shorts. It makes him smile and he closes his eyes, enjoying the sensations.

Will uses both palms, the finger cots feeling a bit weird against his bare skin, but it isn't long before he relaxes, the tension leaving his body as if banished by Will's healing touch.

When Nico feels about as solid as warm butter, Will moves his hands lower and concentrates on rubbing Nico's ass cheeks. He's always loved it when Will touches his butt, but this time, this focus – like Will's seeking out any hidden knots in his muscles and working them loose – goes straight to his cock, ramping up his desire and coaxing stupid-sounding moans from his mouth that are entirely beyond his control.

His face heats up as his cock, trapped along the inside of his thigh, starts to swell. His breathing quickens. And then Will's hands leave his body and his ass is cold. He hears Will uncapping the tube of lube and squirting it into his hand.

Will's voice is low, deeper than usual. "This will feel really cold at first. Are you ready?"

Nico swallows. "Yeah," he says, but it comes out breathy and a little more needy than he meant it to. Will puts one warm hand back on his butt, right over his crack and spreads his cheeks, holding them apart.

It's freezing when the lube touches his asshole, but Will applies it all over, rubbing in circles until it warms and Nico thinks his cock is leaking already. He remembers the towel underneath his hips and closes his eyes again, just letting it happen. Will moves his hands again, applying more lube, and then brings them back, spreading the slickness over his hole and tapping all around his rim. It feels good. Really good. How did he not know how sensitive his asshole was, how many nerves Will is waking up with a brush of his finger tips? He rocks his hips a little, wanting Will to touch him more, deeper. He almost chokes on his own saliva when he realizes what it is he's gagging for and his face flushes hot.

"Is it still okay?" Will asks, slowing his touches, but not stopping. Evidently, Nico can't control his own hips and they buck back against Will's fingers, showing him just how eager Nico is.

"Please," he groans. "Do it."

Will's breaths sound ragged, but Nico doesn't even care. He pushes his hips back until one of the tips of Will's fingers slips inside him. He gasps, wanting more, _more_, harder, but Will pulls his hand free and Nico groans his frustration into the sheet.

The sound of more lube being squeezed out. Will swallowing loudly. The sensation of Will exhaling hard through his nose, blowing his breath in gentle puffs of air on top of Nico's ass. He wants it all. All the sensations, all at once, all the fingers, just _all_.

Then Will's fingers are back, the cool of the lube and finally, a fingertip. He braces himself and then bites his sheet because it's not enough and Will's just using his fingertip to push more lube into his ass. "Will…" he says, gritting his teeth, drawing out his name in annoyance.

More puffs of breath, then Will answers, panting, nearly whimpering. "Yeah, it's just …"

Nico lifts his head and looks back over his shoulder as Will slips his finger inside, rubbing the lube against the walls of his asshole. It's alright, but not spectacular, and Nico focuses on how Will bites his lip, how it looks like he's almost holding his breath. "What's the matter?" Nico asks, and Will looks up, meeting his eyes, all traces of professionalism gone.

Will's eyes burn with longing and Nico feels it deep, almost on a spiritual level. And then Will crooks his finger and Nico swears, dropping his head back on the bed, panting. The jolt of pleasure that shocked his system ebbs back as Will measures his reaction.

"More, again … so good," he mumbles, tempted to rock his hips back and rub his own prostate with Will's finger if the bastard would just leave it there.

Will repeats the touch, brushing over the spot again, flipping his fucking on switch. He snaps his head back, gasping, and Will does it again, and he's just about ready to sing he feels so good, so _alive_.

"You're so beautiful, Nico. I can't stand it," Will says, and pulls his hand free.

Nico furrows his eyebrows, then pushes up on his hands, turning on his side, ready to start talking back and pulling whatever card he can to get one up on Will when Will curls up alongside him, draped over his body. He smashes their mouths together, his hand moving back down, and Nico lifts his leg reflexively, distracted by Will's tongue and hungry lips. Will teases his rim with his fingers again, and pushes two of them inside, sucking Nico's gasp right out of his mouth.

Will finds his prostate at once and begins stroking it with both fingertips. It's all Nico can do to stay present. He feels like he's flying, and then Will wrestles him upright so he's straddling Will's thighs, Will playing him like an instrument. Fingers stroking up inside and a slippery grip around his cock. Nico drowns in Will's eyes, their gazes locked, an inch apart, breathing each other's air through slack jaws, and then Will releases Nico's cock, fumbling his fly open with his hand, pulling himself out with a low moan and barely making it. Hot come splashes up Nico's stomach and chest. He holds himself up, tightly grasping Will's shoulders, controlling the pressure with his thighs, raising and lowering his hips.

Will brushes his prostate again, but instead of moving off it, presses harder, his hand vibrating and Nico comes without a hand on his cock, choked with pleasure as he shoots spurt after spurt of thick white come between their bodies. He feels like a fountain he comes so hard, so long, so _much_, and then Will slips his hand free again, wraps Nico up in his arms and pulls him down on top of himself in a graceless heap.

It feels like forever before Nico feels like he's fully back in his body again. He shivers as his sweat cools, and Will opens his eyes. They're unfocused, like he's half-asleep, but he reaches down, groping, and moving his legs, finally finding the blanket and pulling it up over them both.

Nico pushes his cheek against the skin revealed by the V-neck of Will's surgeon's shirt. He breathes deeply: come-scented air, sweat and arousal cocooned with him under the blanket. Will pulls the finger cots off his hands and hums contentedly, almost like purring.

"I need to get up and get a wet rag soon, Nico. We don't want to fall asleep before cleaning up.

Nico nuzzles Will's chest some more, his eyelids closing on their own. "Mhm. Lotta good the towel did. Gimme five minutes"

XxxX

They don't look too pretty when they wake the next morning. But even decades later, Nico swears that night was the best birthday ever.


End file.
